My compressor is not shutting down. It will get up to about 170 psi, lift the safety and keep on running. I thought it was the pressure switch but I have had other opinions given to me. One being NO175925V valve plate. Why could it be this and how do you check this part to prove it faulty? The other being NO36518 connecting rod assembly, how do I troubleshoot this part? Lastly the pressure switch how can I test this and eliminate it? Any ideals or if you have had a lot of experience with these parts please let me go with it. I know most times there will be one part that causes 90% of all the problems. Anybody have any experience with that? Compressor comes on, runs good, lifts the safety at around 170psi continues to run. I think the tank is pressuring up because of the amount of time it takes the tank to de pressure after the safety lifts.

Hi Sam3322,
The D55141 has a approx cut in pressure of120 PSI and approx cut out pressure of 150 psi. The pressure release valve will blow at between 165-170 psi if I remember right. If your blowing the safety valve off a 170 psi then its a sign that the Pressure Switch
Part Number: N003306SV is defective or clogged.Before you replace it try this first. remove the switch then remove the hose from the switch.Take a paper clip and poke down the pressure switch port and clean any mud or rust that may have gotten down there and clogged the hole.This was a common problem on the d55141.A clogged intake pressure port on the switch was much more common then a defective switch.Hope this helps.Good luck.
Tinker

howdy folks, I have a little dewalt air compressor model d55141 type 1 serial 2768035197 that will not pump past 120 p.s.I. I ordered a new switch fot it part noo3306sv and it is rated for 150 cut out pressure. I was told that this is the correct switch for it, but it just can't get past 120.is there another switch rated at 120 p.s.i.that I can use?. thank you in advance for any help you may be able to give me. grasswhacker

Hi,
Are you saying that it won't pump up past 120 p.s.i. before it shuts off or that it will continually run but not pump past 120p.s.i?

Reply: Compressor Not Building Up Press...

grasswhacker

howdy, I'm sorry for not making myself clear. the compressor will pump up to 120 p.s.I.just fine but cannot pump past that and will continually run. thank you grasswhacker.

Reply: Compressor Not Building Up Press...

Tinkerdave

Hi grasswhacker,
There could be a number of things causing the problem in that model.I'll give them in the order of the most common.
1.The compressor uses a teflon piston ring and this could be damaged.
2. Check the reed valves in the cylinder head and see if they are worn or damaged.
3. Check the red tube ring and see if it is damaged.This red ring is where the tube come out of the cylinder head.
These three things will give you a good place to start in troubleshooting the compressor.Hope that helps.Good luck.
Tinker

After initially starting my 4-5 year old Model D55141 with regulated pressure set for 100 psi, the tank pressure will build to 125 psi. When the compressor kicks on to remain at pressure it "buzzes" for a second or two and then stops without the compressor coming back on. It continues with this buzz on / stop cycle every 5 seconds or so. Meanwhile the regulated pressure starts to slowly fall and never resumes / builds back to the 100 psi setting. Any idea on what might be the problem and on a recommended repair?

I think your pressure switch is okay. I would look more into either the N017592SV Valve Plate. Check for worn or damaged parts. Or it could be the N036518 Connecting rod assembly with the cylinder and rings. It could be worn to the point where air is blowing by and not getting into the tank.

My adjustment knob isn't working properly and my compressor will not exceed 50 psi. I've replaced the air check valve and when I shut it off I no longer hear air escaping, but it still won't exceed 50psi. The knob doesn't seem to work right and when I remove the knob I find a spring inside that sets on a piece of plastic. I'm assumming the spring pushes down on the plastic as the knob is tightened allowing the pressure to be controlled. Do I need to replace the whole manifold or is there another fix for this?

Hi TerryB,
Sounds like what you have is a frozen spool steam in the regulator.Look on the back of the regulator body and see if there is a nut that can be removed. If so remove it and carefully pull out the spool steam and nut.The spool steam should sit in a tube on the bottom of the nut with a small spring in between them. Gently pull the steam from the tube on the bottom of the nut and and you should see a o-ring.This steam with the help of the spring moves back and forth in the tube and regulates how many air psi is allowed to the working side of the regulator..If its frozen then it will not respond to the control knob.If it is frozen then clean it well and apply a little grease to the o-ring and spool reassemble it and place a little grease on the disc you took out with the big spring under it that should get you going.I don't know what compressor you have so i'm not sure of what regulator you have.Some regulators have no nut on the back so the spool comes out the front of the valve body.Hope this helps.Good luck.
Tinker

Reply: Regulator Adjustment Knob

TerryB

I have a Dewalt d55141 Type 1 compressor. Is there a diagram that shows the assembly? I have no nut on the bottom but the knob itself unscrews. There's a large spring and a disc that has an O ring. Under that there's a smaller disc with a spring at the bottom. I'm not sure I'm reasembling it correctly. Does the disc with the O ring go in first and then the big spring or does the big spring go in first and the dis with the O ring sets on top of the spring?

Reply: Regulator Adjustment Knob

Tinkerdave

Hi Terry,
The big spring sits right below the regulator adjusting knob.So you would have your a pressure adjusting knob then the spring then the disk.Hope that helps.
Tinker

Hi homeowner,
The D55141 compressor's pump and motor is a none serviceable unit.It would need to be replaced as a whole unit.Does the compressor pump up to certain level and stay there as the compressor runs or does the gauge just stay on zero and not pump up at all when running.If it pumps up to say 40 psi and sit there while it continually runs you might have a bad check valve Check Valve Part Number: D27022.To check this run the compressor and when it gets up to the maximum pressure that it will pump,shut it off and listen and see if you can hear air leaking out around the pump area.That check valve holds the high pressure in the tank while the pump is pumping air into the tank.If its not working then the tank will push air back into the compressor head until it equals the pump pressure.Hope that helps.Good luck.
Tinker

Reply: Homeowner

TerryB

I got the air check valve and installed it but the compressor still won't exceed 50 PSI. If the regulator knob is defective could that cause the problem? If so do I need to replace the manifold unit or is there another solution?

Reply: Homeowner

Tinkerdave

Hi terryB,
The D55141 is a very light duty compressor.Being that it's an oil less compressor its duty cycle is rather low.It can't deal with thermal issues very well so if one happens to use the compressor on a job where the compressor has to run on a continual bases then there is a chance that the pump won't dissipate the heat fast enough and the teflon piston ring will get too hot and peal part of the way off the piston and preventing the piston from making a good seal.The degree to which the teflon ring peals back would determine how much pressure is built up before it stops building up pressure in the tank.
If you take the pump apart I bet you'll find a damaged piston ring and cylinder or a broken reed valve.The problem is you would have to replace the whole pump assembly.Hope this helps.Good luck.
Tinker

The compressor is a couple of years old. The compressor runs fine, but sometimes after it runs up to 150psi and the compressor kicks off, the air will leak down until the kick-on threshold. Sometimes the air will stay in and sometimes not. The leak is somewhere right around the compressor (inside the black box).

It seems like a check valve somewhere is sticking intermittently, but I'm not sure which one and/or where.

Has anyone had any experience with this, or know which part I need to replace? Thanks.

Hi Wedgefield, Most of the time its Part Number: D27022 check valve that does not seal all the time.Check that first. Hope that helps.
Tinker

Reply: Dewalt D55141 Compressor

Stryker223

My compressor does that every now and then and the reason for it is not the check valve! The aluminum tube that comes off the pump is so slick, the rubber hose slides off it no matter how much clamping pressure I put on it. I just have to remove the pump unit and slide the hose back onto the tube and clamp it back on and I'm good for a few months. The next time it happens I think I might try some super glue, lol!
Take care
Michael

There is a small pressure relief valve on the large brass fitting where the air enters the tank from the pump on my D55141. Air leaks out of the small hole on the top of it all the time. It is easy to replace, but I don't see it listed. Anyone know the part number, and where to get it?

My compressor pumps air till the safety value blows and continues to run till it blows again over and over. I seen other had this problem and the diagnosis was pressure switch. I ordered and changed the pressure... no difference. I am at a loss.

I've got the same problem! And it looks like others do to. I don't know how to fix this either.

Reply: D55141 Compressor

1204805

Did you get the problem fixed? What was wrong with it? mine is doing the same thing.

Reply: D55141 Compressor

Tinkerdave

Hi Ben and Herb,
The pressure switch has cut in pressure of 120 PSI (This is the pressure the unit should turn back on) and a cut out pressure of 150 PSI (This is when the compressor should shut off) The blow out safety valve should activate at around 160-170 psi.Is the blow out safety valve being activated under 150 PSI? If so your safety valve is bad. If its being activated over 160 your pressure switch is bad.They made two pressure switches for the type 1 and the type 2,3,4,5.Your showing the type 1 which should be the N003307SV.Not the N003306SV.
Also that series of compressor had a problem if the tank was not drained after every link removed and slag would work down the pressure switch tube clogging it and not allow pressure to get to the switch thus allowing it to build up enough pressure to kick the safety valve on.Most of the time the switch air inlet would be filled with mud and dirt.
check these thing out and if you still have a problem let us know and we will take you through the next trouble shooting steps.Hope that helps.Good luck.
Tinker

I experienced the same problem with my DeWalt D55141 compressor. The air leaks when the pressure reaches 80 to 100 psi. I saw a small hole on the outside of the head if you shine a light from the other side of the head. I filled the hole on the outside using epoxy pudding that I bought at a hardware store.

Reply: Losing Air

Mark

Hi Donnie and Greg,

The hole on the side of the head should be there. It is a pressure release hole to guard against a bad check valve. If the check valve fails, air from the tank will bleed back to the cylinder. With the tank pressure pushing back on the piston the motor must work much harder and will heat up and fail. The hole must not be blocked. Replacing the check valve should solve the air leak. The check valve is part #D27022 and is available from http://www.ereplacementparts.com.

My compressor looses air while compressing. This continues after it shuts off. When it tries to restart the pressure on the compressor is too high and the motor stalls. Is this because of a sticking check valve or is there an unloader valve I don't see. Help.

MY COMPRESSOR HAS BEEN RUNNING SLOWLY AND SMOKING SO I TOOK IT APART AND NOTICED QUITE A BIT OF ARCHING FROM THE BRUSHES. THE ARMATURE WAS DIRTY SO I CLEANED IT AND THE BRUSHES TOO. PUT IT BACK AND SAME AMOUNT OF ARCING?
THERE DOESN'T SEEM TO BE ANY SHORTS OR LOOSE WIRES. IS IT POSSIBLE THAT THE ARMATURE IS BAD? WHAT ELSE SHOULD I TRY?

The arching is caused by a shorted out armature. DeWalt does not offer individual parts for the motor on this compressor. You will need to purchase the motor and pump assembly to make the repair. The motor and pump assembly is part #A16342 and is available from http://ereplacementparts.com.

It sounds like you have a bad pressure switch. The pressure switch is the part that senses when the compressor has filled the tank to a certain pressure at which point it cuts the power to the motor. The pressure switch is part #A05802 and is available from http://ereplacementparts.com.

I have air compressor D55141. This compressor is running and running never make stop, when the valve pressure past 130 the valve safety is open and continued running.
How I can repair and what is the part need replaced?

It sounds like your pressure switch has failed and will need replacing. It is item #312 on page B of the parts diagrams. The pressure switch is part #A05802 and is available from http://ereplacementparts.com.

Most likely there is a small hole in the head casting. Replacing the head should solve the problem. You should need parts D29146, head and Z-D24819, head gasket. You should be able to easily do this repair. Form the pic it looks like you have already done all of the hard work!

I own a D55141 compressor and it will no longer compress beyond 45 psi. There does not seem to be an air leak anywhere and the motor never turns OFF. When I disconnect the power and air hoses, the tank will keep the low psi forever...it this a problem with the pump regulator?

Hey misomosi,
most likely it is your piston/sleeve assembly..it is just wore out and needs replaced..check out the breakdown on ereplacementparts.com to where it is located..[page two] part # kk-4964 .. you may want to take this in to a repair shop if you are unfamiliar with this type of repair..hope this helps?:)
Craig

Reply: Dewalt D55141 Air Compressor

Misomosi

Craig, thx for the quick response. This is great information.
-Mike.

Reply: Dewalt D55141 Air Compressor

calderongil

Hello:
Somebody can help me to know: For how much pressure (psi) goes off the air compressor model Dewalt D55141 ?
Thank you for your answer.
Regards,

Hey Mrromero,
Chances are you will need to replace the piston/rod assy part# kk-4964 ..
the leatherlike ring wears out on the piston head and the cylinder wears out also..sold in a kit form..ereplacementparts.com $29.75...
check out the parts breakdown..it is reference # 325...
hope this helps..:)
Craig

I originally bought the compressor because it was much quieter than any other I could find. It worked very well for a while, but then wouldn't start because it was trying to start against the pressure head. The relief valve wasn't working. Since I live a two hour drive from the nearest service center, it would have been two hours up, two hours back, wait for several days and then two hours up and two hours back, I decided to see what I could do. With a little shaking and banging the relief valve let go and we were up and running. This was good for a month when it just plain stopped. Faced with the same scenario I decided I'd take it apart and see if I could find the problem. (I've done this with many problem machines in the past.) I found that one of the brushes was hung up. I monkeyed with it and got the brush to seat and off it went. Good for another couple of months. Stopped again. Same problem. Ordered new brushes, but when brushes hang up or bump on the commutator the commutator is damaged so this fix might not work. The brushes sent were the wrong ones, but they don't offer any others so I tried them. No go. So I decided to order a whole new motor assembly. Guess what. The motor assembly costs $235 plus shipping. Now if you didn't notice, that is more than the cost of a new unit. I tried to point this out to the folks at DeWalt, but never got any where.